I’m one of the rare few who needs only 4 hours of sleep per night

Physician Sindi van Zyl is a natural short sleeper, the rare person who doesn’t need caffeine, naps—or delusional thinking—to thrive on limited sleep.

I’m one of the rare few who needs only 4 hours of sleep per night
[Photo: Wavebreakmedia/iStock]

Sindi van Zyl, 43, is a physician based in Johannesburg, South Africa, who specializes in treating HIV patients. After hours, she hosts a radio show. She’s also a wife, a mother to two kids, and a prolific tweeter. How does she get it done? As a short sleeper who needs no more than four hours of shut-eye, she has something of a leg up on the rest of us.


Van Zyl, along with less than 3% of the population, is a natural short sleeper, someone who can fire on all cylinders with far less sleep than the average person—without the aid of stimulants, naps, or delusional thinking. Most people who think they can get by on four hours of sleep are chronically sleep-deprived and hopped up on caffeine. It’s the rare person whose genes dictate that they’re too busy to sleep.

We spoke with van Zyl about how she realized she was a natural short sleeper, what she does with all that extra time, and whether she even knows what it feels like to be tired.

“I was worried there was something wrong with me”

All my life, I’ve always known that my sleeping pattern wasn’t like everyone else’s. I remember that in boarding school, I’d be the one who was up at the crack of dawn. I would go downstairs and shower and then go and wake up my friends. And it irritated them so much. Why was I up early and so bright and spritely when everyone else was sleeping and tired?

In 2012, I went to a talk that was given by sleep researcher and clinician Alison Bentley. She was giving a talk about how sleep deprivation was used as a form of torture in torture camps. After the talk, I managed to get a chance to talk to her. I explained to her that I have a problem and think I need help because I don’t sleep much. I generally sleep four hours a night, and then I’m up and good to go. It doesn’t matter what I’ve done the night before, or what I’ve done during the day. As soon as my four hours is up, I’m awake. At least once or twice a month, I’ll sleep for six hours, and it’s as if my batteries have been recharged.

I was worried there was something wrong with me. She started laughing and said, “Oh no, there’s nothing wrong with you. You’re one of the special people who’s a short sleeper! And it’s a genetic thing—chances are one of your parents is like this. There’s nothing wrong with you. That’s just who you are.”


“I’m up between 2 a.m. and 3 a.m. in the morning”

I finish my radio show at 8 p.m., and I get home at 9 p.m. I’ll chat with my husband a bit and have something to eat. I’ll do an hour or so of Twitter and then sleep at 10 p.m. Then I’m up between 2 a.m. and 3 a.m. in the morning. I don’t like coffee, so I don’t drink it. I don’t take energy drinks either. I love water and mostly drink water—and of course, I love champagne, as well.

On Twitter, we have what we call the “insomnia gang.” There’s a bunch of us that are always awake at a certain time, and we know each other and greet each other. If I’m not tweeting, it’s because I’m holding myself back.

I now work around my short sleep. I wake up and run errands; I found a 24-hour grocery store and 24-hour car wash. By the time people wake up at six in the morning—say, I’ve woken up at two—I’ve done so much. I really have a head start to my day. But I do spend a lot of time on Twitter, I must admit. I’m trying to start reading books again because Twitter has made me so lazy.

“The whole concept of sleeping for eight hours is just a foreign one”

When I used to do night shifts, I found that I could work late into the night. We worked 36-hour shifts, but I could go back and get an hour of sleep and then be up again, bright and perky. I wasn’t grumpy or tired post-call. As long as I had my one or two hours of sleep, I was refreshed and I was good to go.

I could go out on a Saturday night and be out until 4 a.m. in the morning. But within three or four hours of sleeping, I’m awake. I wake up fully rested; I wake up as if nothing happened. Everyone else is still groggy and tired and hung over or whatever. But I’m awake awake.


The whole concept of sleeping for eight hours is just a foreign one. I can’t imagine being in bed for eight hours. What are you doing? The world is passing you by.

“My dreams get interrupted so that I can wake up”

Sometimes I’ll be dreaming something, and then something will happen in my dream that forces me to open my eyes. I don’t know if this makes sense, but my dreams get interrupted so that I can wake up.

One time in a dream, I was shopping—and the shopping was going well. But someone tapped my shoulder in the dream and startled me, and that woke me up. I looked at the time, and it was my wake-up time.

“At least once a month, I have a long sleep”

Once or twice a month, I have what Alison terms a “recharge sleep,” where you sleep longer than normal. You sleep for six hours or, for some people, seven hours. And then from there, the pattern carries on. So at least once a month, I have a long sleep.

I’m living with depression, and one of the things that alerted me to the fact that there was something wrong with me was that I was sleeping a lot. But at the time, I didn’t realize I had clinical depression. I went from sleeping three to four hours a night to sleeping six to seven hours a night. And I knew then in my heart, “Oh my gosh, something is wrong with me.”


I didn’t have the will to get out of bed and do anything. But also, you’re so occupied with wanting to die. A lot of people who are depressed spend a lot of time sleeping. You’re sleeping, but sometimes you’re awake and just in bed, and all you can think of is: “I hope I never wake up.” You don’t want to wake up because you don’t feel there’s anything to wake up for.

“I don’t know that I really know what tired is”

I like telling people I’m feeling tired, but I don’t know that I really know what tired is, to be honest. I’ll get home and I’ll say to my husband, “Oh, I’m so tired, I had a long day at work.” I’ll go to bed and sleep for an hour—and then I’ll wake up and be on Twitter for the next five hours.

When I visited New York, we walked around the perimeter of Central Park. My legs were sore; I was grumpy and hot. I was annoyed, and I was tired. I know how that kind of tired feels. But I’m not sure I know the feeling of, “I need sleep now.” I don’t know that I really, truly know how that feels.

The shortest sleep I’ve ever had was two hours. I went to bed at 9 p.m. and when I woke up, I honestly thought I could hear the birds singing. I checked my phone and was like, ‘Oh my goodness.” I woke up at 11:06 p.m. It wasn’t even midnight! I was so disappointed and mad because I knew I wouldn’t be able to go to sleep again.

“It can disrupt your partner’s sleeping habits”

My husband is such a kind guy and so patient with me. He’s a computer programmer, so he also works in the wee hours of the morning. He wakes up easily, so when he needs to get a proper sleep, he or I will sleep on the couch. He’ll say to me, “Tonight I need to get proper sleep, so you can’t wake me up and nudge me, or wake me up with the glow of your phone.” I think that’s the only disadvantage—the fact that it can disrupt your partner’s sleeping habits.


“If you need to sleep, you must sleep”

When I tweeted about being a natural short sleeper, someone asked me how they can make themselves one. I said to them, “I was born like this. I inherited this from my parents.” I don’t encourage people to do that. If you need to sleep, you must sleep. Otherwise, you’ll be grumpy and irritable and start making mistakes. Get your six to eight hours in, and make it good sleep. Don’t try and force yourself to run on little sleep.

About the author

Pavithra Mohan is a staff writer for Fast Company.